* {
  margin: 0px;
  padding: 0px;
  font-family: Arial, Helvetica, sans-serif;
  /* 内减盒子 */
  box-sizing: border-box;
}
body {
  font-size: 12px;
}
li {
  list-style: none;
}
img {
  vertical-align: middle;
  /* 图片居中 */
}
a {
  color: #000;
  /* 取消a标签默认下划线 */
  text-decoration: none;
}
input {
  border: 0 none;
  outline-style: none;
  /*取消内边框*/
}
.fl {
  float: left;
}
.fr {
  float: right;
}
/* 清除浮动，解决margin-top塌陷 */
.clearfix:after {
  content: "";
  display: block;
  height: 0;
  clear: both;
  visibility: hidden;
}
.clearfix {
  zoom: 1;
}
